\ example of edge-rewriting system for L-machine
\ This one implements a type of non-self-intersecting curve
\ Called a Hilbert Curve.

n = 3
delta = 90.0
X0 = 220.0
Y0 = 10.0

initial = -L   \ initial = turn left, left turn

\ define macros for turtle

macros

R = -F+F+F-
L = +F-F-F+

endm

rules

L = LF+RFR+FL-F-LFLFL-FRFR+
R = -LFLF+RFRFR+F+RF-LFL-FR

endrules
end